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Topic: Switching Relay #1 (Transfer Switch) (Read 659 times) previous topic - next topic

Switching Relay #1 (Transfer Switch)

We may have a problem with Switching Relay #1 (Transfer Switch).  On two different occasions about a week apart in the evening while we were watching television we hear a "thunk".  The same type of "thunk" when one first plugs in the rig and flips the 50VAC breaker. When the "thunk" occurs the DirecTV satellite receiver goes off momentarily and then starts the long process to reset itself.  Also the television goes off during this momentary loss of power.  The momentary loss of power isn't enough to mess with the microwave clock or the bedroom clock radio display.  A check of the Progressive surge protector at the power pole shows no problem with shore power.  Switching Relay #1 is located in the bay housing the Prosine converter/inverter, 12VDC air compressor, HWH components and 12VDC wiring panel.  The bay is on the driver's side just back of the driver's seat.  I opened up the transfer switch box (see pictures).  Don't see any issues.  Wondering if I need to tweak the orange voltage monitors?  There are set screws, but couldn't find any instructions on the Internet.  Help!!  Any ideas what might be the problem?
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Switching Relay #1 (Transfer Switch)

Reply #1 –
What are your voltage when this happens?  We were at a state park in Nebraska and this happened. I called the Maverick company and talked to a tech. He told me that I could turn the dial on the pot to raise the cut off. We had high voltage. I raised it to 132. Later that evening it shut down again. I checked at the pole and it was 137. I unplugged and ran the generator the rest of the night and then left in the morning. It will also cut off with low voltage so you need to check what it is.
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previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
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Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Switching Relay #1 (Transfer Switch)

Reply #2 –
To set those orange over/under relays, you need a calibrated/known verified voltage source so you can set under at 108 and over at 132.  That is not a campground hookup voltage - you need a controlled supply to set them properly.

Those relays do go bad.  I believe they are MilSpec, so you'd be looking for government surplus.

That said, you could be experiencing an actual shore power issue, so I would not be quick to touch them, especially if this is a new occurrence and it has only happened at this location.  Verify there isn't something else causing voltage droop or spike first.  They might pick it up faster than the Progressive EMS (I don't recall its response sensitivity).
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Switching Relay #1 (Transfer Switch)

Reply #3 –
Thanks for the responses.  I am unaware what the voltage readings were when the incidents occurred.  At the time of the incidents I didn't think to look at the power line monitor, just wanted the DirecTV unit to reset itself so we could continue watching our program.  In any case, voltage readings on the power line panel do not reflect what the Progressive unit reads.  In the past at another campground the Progressive unit shut off power to the coach when the CG power supply experienced a low/high voltage event.  Had to switch off the power pole breaker to reset the Progressive unit.  These two incidents this past week did nothing to the Progressive unit.  According to the Progressive instructions their unit should shut down power in less than one nano second.  Maybe the Progressive unit is defective?  If we experience this again at another campground then we'll know it's an issue with the coach and investigate further.  Since I have no way of adjusting the voltage meters inside the transfer switch, maybe I could just disconnect them and just rely on the Progressive unit to keep the coach safe from electrical disturbances?  Thoughts?
David & Sherry Kendrick
"Gizmo" The Doggy Lama
USAF(Ret) 1971-75; 1979-95 (20 yrs)
2003 U320 F03 [6179] 38PBDS (3/2016)
2016 Chev Silverado Z71 LTZ
Motorcade 17738
--------------------------------------
New Horizons 5W 25' RKS (1/2004 - 3/2016)
2003 Chev Silverado 2500HD Duramax
Tent (5-person) White Stag (1972 - 2003)

Re: Switching Relay #1 (Transfer Switch)

Reply #4 –
If you want to keep Directv receiver working through power switching, install a dedicated inverter for your Directv receiver, wiring the 12v side to house battery bank. Many have done this. Also eliminates brown out low voltage damage for delicate electronics by insuring a constant correct 120v.

Re: Switching Relay #1 (Transfer Switch)

Reply #5 –
Or use the quick and dirty way and buy a cheap UPS. "uninterrupted power supply" that is what I am doing until I get the dedicated inverter in. Going on 2 years now.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
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Re: Switching Relay #1 (Transfer Switch)

Reply #6 –
Quote from: WagonWheels –
If we experience this again at another campground then we'll know it's an issue with the coach and investigate further.  Since I have no way of adjusting the voltage meters inside the transfer switch, maybe I could just disconnect them and just rely on the Progressive unit to keep the coach safe from electrical disturbances?  Thoughts?

The only way to know is to measure.  "We" used to own an operate a 3-phase recorder with pens and paper tape, doing a quick Google search brought up this little gem.  Since a 50A RV uses two power supply lines, you'll probably need to spring for a multi-phase recorder.

Powertronics Probe 100+ - USB Power Line Monitor, Black - Voltage Testers -...
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